It is a common belief that mathematics is a difficult subject from the standpoint of teaching and learning. A majority of students, especially at the secondary level, dislike mathematics and the mathematics teachers are held in high esteem by the students. A Portion of student tries to escape from the mathematics class since it involves a lot of mental exercise. What are the reasons for this state of affairs? Does mathematics need a special type of mantal capacity for successful mastery of its rules and principles? This Question has been of immense interest for mathematicians and mathematics education. It has a long research history. Many researches have been carried out by researches in the area. The purpose of the present book is to summarize such research findings and to interpret them in order to identify what exactly the nature of mathematical ability Is. The book is more of a psychological orientation than mathematical. The ideas have been presented in a simple language. It is expected that the book will prove to be of a great interest and help to research scholars, mathematicians, teachers of mathematics, curriculum planners and teacher education.